Mergers and Acquisitions - Prelimnary fair value and adjustments (Details) - USD ($) $ / shares in Units, $ in Thousands	Jan. 01, 2025	Mar. 31, 2025	Dec. 31, 2024
ASSETS
Investment securities		$ 8,395,044	$ 6,798,876
Loans held for sale		357,918	279,426
Loans		46,143,042	33,437,647
Premises and equipment, net		946,334	502,559
Bank owned life insurance ("BOLI")		1,273,472	1,013,209
Deferred tax assets		153,930	179,884
Goodwill		3,088,059	1,923,106
Core deposit and other intangibles		455,443	66,458
Other assets		650,117	433,755
Total assets		65,135,454	46,381,204
Deposits:
Noninterest-bearing		13,757,255	10,192,117
Interest-bearing		39,580,360	27,868,749
Total deposits		53,337,615	38,060,866
Other liabilities		980,157	598,295
Total liabilities		56,511,093	40,490,789
Goodwill		3,088,059	1,923,106
Assets
Goodwill		3,088,059	1,923,106
Deposits:
Goodwill		3,088,059	$ 1,923,106
Independent
ASSETS
Cash	$ 1,040,878
Investment securities	1,590,452
Loans held for sale	12,430
Loans	13,008,357
Premises and equipment, net	315,674
Bank owned life insurance ("BOLI")	252,001
Deferred tax assets	114,563
Bank property held for sale	72,000
Goodwill	1,164,953	1,200,000
Core deposit and other intangibles	412,078
Other assets	155,587
Total assets	16,974,020
Deposits:
Noninterest-bearing	3,238,170
Interest-bearing	11,970,543
Total deposits	15,208,713
Shot-term borrowings	360,522
Other liabilities	96,677
Total liabilities	15,665,912
Net identifiable assets acquired over liabilities assumed	1,308,108
Goodwill	1,164,953	1,200,000
Net assets acquired over liabilities assumed	2,473,061
Assets
Goodwill	1,164,953	1,200,000
Deposits:
Goodwill	$ 1,164,953	$ 1,200,000
Consideration:
SouthState Corporation common shares issued	24,858,731
Purchase price per share of the Company's common stock	$ 99.48
Value of shares issued	$ 2,472,947
Value of common stock issued for fractional shares	114
Fair value of total consideration transferred	2,473,061
Independent | Adjusted Acquired Balance Sheet
ASSETS
Loans held for sale	12,430
Assets
Cash and cash equivalents	1,040,878
Investment securities	1,647,163
Loans, net of allowance and mark	13,453,678
Premises and equipment	381,204
Bank owned life insurance	252,001
Deferred tax asset	79,189
Goodwill	476,021
Intangible assets	38,808
Other assets	167,117
Total assets	17,548,489
Deposits:
Noninterest-bearing	3,238,170
Interest-bearing	11,968,821
Total deposits	15,206,991
Other borrowings	354,713
Other liabilities	101,165
Total liabilities	15,662,869
Net identifiable assets acquired over (under) liabilities assumed	1,885,620
Net assets acquired over liabilities assumed	1,885,620
Consideration:
Investment securities	1,647,163
Premises and equipment	381,204
Interest-bearing	11,968,821
Independent | Preliminary Fair Value Adjustments
ASSETS
Investment securities	(56,711)
Loans	(445,321)
Premises and equipment, net	(65,530)
Deferred tax assets	35,374
Bank property held for sale	72,000
Goodwill	1,164,953
Core deposit and other intangibles	373,270
Other assets	(11,530)
Total assets	(574,469)
Deposits:
Interest-bearing	1,722
Total deposits	1,722
Shot-term borrowings	5,809
Other liabilities	(4,488)
Total liabilities	3,043
Net identifiable assets acquired over liabilities assumed	(577,512)
Goodwill	1,164,953
Net assets acquired over liabilities assumed	587,441
Assets
Investment securities	56,700
Premises and equipment	65,500
Bank property held for sale	72,000
Goodwill	1,164,953
Goodwill	(476,021)
Deposits:
Interest-bearing	1,700
Goodwill	1,164,953
Consideration:
Investment securities	$ 56,700
Percentage of preliminary credit mark	1.60%
Amount of preliminary credit mark	$ 214,800
Percentage of total preliminary credit mark	4.40%
Amount of total preliminary credit mark	$ 600,600
Amount of allowance for credit loss of acquiree	133,000
Amount of fair value adjustments of acquiree reversed	22,200
Premises and equipment	$ 65,500
Fair value adjustments with effective tax rate	23.50%
Bank property held for sale	$ 72,000
Amount of gross core deposit intangibles	$ 412,100
Percentage of gross core deposit intangibles	3.60%
Amount of existing core deposit intangibles	$ 38,800
Value of real estate asset repossessed	4,200
Amount of write off of prepaid expenses and other miscellaneous assets	7,300
Interest-bearing	1,700
Amount of discount and issuance costs of debt	7,600
Net discount	1,800
Amount of existing reserves for unfunded commitments	2,900
Amount of fair value adjustments of lease liability	2,200
Amount of adjustments for miscellaneous accruals for lease liability	660
Independent | As previously recorded by acquiree
ASSETS
Cash	1,043,293
Investment securities	1,644,381
Loans held for sale	12,430
Loans	13,452,928
Premises and equipment, net	348,071
Bank owned life insurance ("BOLI")	252,001
Deferred tax assets	72,362
Goodwill	476,021
Core deposit and other intangibles	38,808
Other assets	226,032
Total assets	17,566,327
Deposits:
Noninterest-bearing	3,241,446
Interest-bearing	11,966,362
Total deposits	15,207,808
Shot-term borrowings	354,713
Other liabilities	95,409
Total liabilities	15,657,930
Net identifiable assets acquired over liabilities assumed	1,908,397
Goodwill	476,021
Net assets acquired over liabilities assumed	1,908,397
Assets
Goodwill	476,021
Deposits:
Goodwill	476,021
Independent | On The Line Adjustments
ASSETS
Deferred tax assets	6,596
Other assets	(23,000)
Total assets	(16,404)
Deposits:
Other liabilities	6,859
Total liabilities	6,859
Net identifiable assets acquired over liabilities assumed	(23,263)
Net assets acquired over liabilities assumed	(23,263)
Independent | Reclassifications and Other Adjustments
ASSETS
Cash	(2,415)
Investment securities	2,782
Loans	750
Premises and equipment, net	33,133
Deferred tax assets	231
Other assets	(35,915)
Total assets	(1,434)
Deposits:
Noninterest-bearing	(3,276)
Interest-bearing	2,459
Total deposits	(817)
Other liabilities	(1,103)
Total liabilities	(1,920)
Net identifiable assets acquired over liabilities assumed	486
Net assets acquired over liabilities assumed	$ 486